Brief Description of the Prior Art
To produce resist patterns or resin patterns as master plates upon production of semi-conductor elements or production of printing plates, there has been hitherto used generally a method which comprises forming a resin film capable of being polymerized or decomposed upon exposure to light on a base plate, exposing the resin film pattern-wise and then developing to form optional patterns. However, the demand for making these resist or resin patterns more minute has been increasing because of requirements for high density of semi-conductor elements and high quality of printed matters.
Particularly in the production of VLSI, it is necessary to produce resist patterns of a submicron level with good accuracy.
In such a case, although it is also greatly affected by physical properties of resist resins per se, generally speaking, a thickness of resist to be coated must be made thin as one wishes minute patterns, namely, in order to increase a resolving power. On the other hand, to make patterns of a submicron level, wet etching is inapplicable but dry etching techniques such as ion etching, plasma etching, sputter etching, etc. must be used. In order to improve dry etching resistance of resist patterns, however, a thickness of resist coated must be generally thickened although it depends on resist materials.
For satisfying the two requirements described above, it may thus be sufficient to develop photoresists having a good resolving power even in a thick coating or photoresists having good resistance to dry etching resolving power; however such materials have not been found so far.